Status epilepticus (SE) is recognized as a major medical and neurological emergency associated with a high morbidity and mortality. Despite the clinical importance of SE, research regarding the frequency, precipitating events and prognosis of SE has remained an underdeveloped area, because of difficulties in studying SE. This research effort is focused on addressing this need and provides a unified population-based study across all age groups in Richmond, VA. Results during the last granting period provided the first epidemiological prospective, population-based study of SE. In addition to developing epidemiological information on SE, this study identified several novel findings that have opened exciting new aspects of research into SE. In addition to developing epidemiological information on SE, this study identified several novel findings that have opened exciting new aspects of research into SE. These new findings represent challenging areas of future research that are the focus of the specific aims in this research project. Having developed and validated this data base, the Richmond study is poised to make fruitful contributions to our understanding of this condition. The CENTRAL HYPOTHESES for the proposed studies are related to information obtained and analyzed from the development of this large data base for SE in the Richmond population. To test these hypotheses, we will accomplish the following specific aims: 1) maintain a prospective, population-based data base for epidemiological studies of SE in the GRMA; 2) further investigate the contribution of etiology to mortality of SE; 3) evaluate variation in incidence, mortality and clinical presentations of SE in high risk populations (the very young, the elderly, and non-white populations); 4) study the epidemiology, morbidity, mortality and prognostic outcome of SE in the neonatal population; 5) use the GRMA data base to compare the incidence and presentation of SE and seizures of various duration lasting up to 30 minutes; 6) evaluate the effects of clinical variables and their interactions in determining mortality in SE, using both univariate and multi-variate logistic regression models; and 7) develop the Richmond Outcome Scale to predict mortality in SE and test this scale for predicting mortality in a prospective fashion. To the best of our knowledge, this prospective, population-based SE data base across all age groups represents the only one of its kind in the world. The use of this prospective population-based data base will provide insights into specific predictive indicators are associated with mortality and that and that may play a role in identifying SE patients at high risk for morbidity and mortality.